Pass the Purple:
The Potential Health Benefits of Purple Corn |
By Kenneth
Jones
Copyright©2003
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There’s a lot more
to those dark purple corn chips you’ve been munching
on than taste. Purple corn is fast approaching classification
as a functional food – an integral component of the
diet that is understood as contributing added health benefits
beyond the simple health benefit of being a food. Researchers
in the fields of food and nutrition are intensely searching
for functional foods in almost every corner of the world.
Their focus is on polyphenolic substances, such as those found
in purple corn and green tea, soy isoflavones, compounds in
nuts, carotenoids, fish oils, and various other natural substances
in our diet with antioxidant and other potential disease-preventive
properties, and especially those that could help to prevent
cancer and heart disease. |
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The purple corn I speak of
is botanically the same species as regular table corn (Zea
mays L.). Yet by a twist of nature, this corn produces kernels
with one of the deepest shades of purple found anywhere in
the plant kingdom. Research has shown that purple corn contains
cell-protecting antioxidants with the ability to inhibit carcinogen-induced
tumors in rats. All well and fine you say; lot’s of
plant-derived substances do that. Yes, but how many also hold
the potential of ameliorating high blood sugar and preventing
obesity? |
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| The kernels of purple corn (maiz morado) have
long been used by the people of the Peruvian Andes to color
foods and beverages, something we in the industrialized world
are just getting around to. They also make a drink from the
kernels which they call “chicha morada”.1 What gives
this corn its deep eggplant-purple color is being seriously
eyed as part of a new class of food-coloring agents with a difference:
color plus health benefits. |
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The source of this natural
alternative to synthetic food dyes is a large group of natural,
water-soluble colorants known as “anthocyanins”.2
Anthocyanins belong to an even larger class of plant chemicals
known as flavonoids and are found in diverse plant-foods including
red grapes,3 black chokeberries, elderberries, and strawberries,4
red onions,5 black beans and red beans,6 and, no surprise,
blueberries. |
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The anthocyanin content of
whole, fresh purple corn from Peru was found to be 16.4 mg/g,
which was much higher than fresh blueberries (1.3-3.8 mg/g),
and the capacity of purple corn extract to scavenge free radicals
was greater than that of blueberries (Cevallos-Casals and
Cisneros-Zevallos, 2003). |
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Digging deeper, the most
abundant anthocyanin found in purple corn,8,9 called “C3G”
(3-O-?-D-glucoside), has been keeping researchers very busy
of late. In a number of tests designed to detect the potential
health benefits of this anthocyanin, one study after another
has found that C3G looks very promising. Red wine also contains
appreciable amounts of C3G,10,11 so you can imagine the interest. |
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